Chang Pahn-Shick, Lee Jonghyuk, Lee Jaehwan
Department of Food Science and Technology, Seoul National University of Technology, Korea.
J Agric Food Chem. 2005 Sep 21;53(19):7385-9. doi: 10.1021/jf051015p.
Microencapsulation of alpha-tocopherol effectively protects alpha-tocopherol from oxidation and produces high-value-added and long-shelf-stable foods. High-performance liquid chromatography (HPLC) has been applied to measure the yield of microencapsulated alpha-tocopherol with high accuracy; however, it takes long analysis time. An alternative method is required to determine the yield of microencapsulated alpha-tocopherol in food industry. A new, easy, and sensitive colorimetric method using 5% cupric acetate pyridine and oleic acid was developed. Correlation coefficient (r) of colorimetric method on alpha-tocopherol in microencapsulation system and of results between colorimetric method and HPLC were +0.996 and +0.989, respectively, which indicates that this novel colorimetric method can be successfully applied to evaluate the yield of microencapsulated alpha-tocopherol instead of HPLC. The optimum storage temperature and pH of microencapsulated alpha-tocopherol for 7-day storage were 25 degrees C and pH 9, respectively, determined by this new colorimetric method.
α-生育酚的微胶囊化能有效保护其免受氧化，并生产出高附加值且货架期长的稳定食品。高效液相色谱法（HPLC）已被用于高精度测量微胶囊化α-生育酚的产率；然而，其分析时间较长。食品工业需要一种替代方法来测定微胶囊化α-生育酚的产率。一种使用5%醋酸铜吡啶和油酸的新型、简便且灵敏的比色法被开发出来。微胶囊化体系中比色法对α-生育酚的相关系数（r）以及比色法与HPLC结果之间的相关系数分别为+0.996和+0.989，这表明这种新型比色法可以成功地用于评估微胶囊化α-生育酚的产率，以替代HPLC。通过这种新的比色法确定，微胶囊化α-生育酚储存7天的最佳储存温度和pH分别为25℃和pH 9。
